Linear drive assembly

Abstract

A linear drive assembly configured for use within a power end assembly. The linear drive assembly is configured to interconnect a crankshaft and a pony rod and comprises a crosshead assembly attached to a connecting rod assembly. In one or more embodiments disclosed herein, the connecting rod assembly is configured to attach to opposite sides of the crosshead assembly so that no portion of the connecting rod assembly is disposed within an interior of a crosshead included in the crosshead assembly.

The invention claimed is: 
     
         1 . A linear drive assembly, comprising:
 a crosshead configured to reciprocate within a guide, the crosshead comprising a bore formed therein;   a connecting rod, comprising:
 a first end; 
 a second end comprising a plurality of linking elements, in which each linking element comprises an opening that is aligned with the bore of the crosshead; and 
 a body interconnecting the first end and the second end; 
   a wrist pin situated within the bore and each opening of the plurality of linking elements; and   a plate attached to the crosshead, the plate comprising a plurality of grooves formed therein;   in which the plate is formed from a first material and the guide is formed from a second material.   
     
     
         2 . The linear drive assembly of  claim 1 , in which the second material is harder than the first material. 
     
     
         3 . The linear drive assembly of  claim 1 , further comprising:
 a second plate attached to the crosshead, the second plate comprising a plurality of second grooves.   
     
     
         4 . The linear drive assembly of  claim 1 , further comprising:
 a first retainer plate and a second retainer plate, each retainer plate engaging the wrist pin.   
     
     
         5 . The linear drive assembly of  claim 4 , in which the plurality of linking elements in the connecting rod are situated between the first and second retainer plates. 
     
     
         6 . The linear drive assembly of  claim 4 , further comprising a threaded pin, in which the threaded pin is disposed through the first retainer plate and joined to the wrist pin. 
     
     
         7 . The linear drive assembly of  claim 1 , in which the crosshead comprises an outer surface having a groove formed therein; in which the plate further comprises a flange that is situated within the groove. 
     
     
         8 . The linear drive assembly of  claim 1 , in which the wrist pin comprises a first end and an opposed second end, in which both the first and second ends of the wrist pin extend from the bore of the crosshead. 
     
     
         9 . A power end assembly comprising a crosshead section, in which the crosshead section comprises a plurality of the linear drive assemblies of  claim 1 , each linear drive assembly attached to a crankshaft. 
     
     
         10 . A pump, comprising:
 the power end assembly of  claim 9 ; and   a fluid end assembly attached to the power end assembly by a plurality of stay rods.   
     
     
         11 . The pump of  claim 10 , further comprising:
 a plurality of stay rod sleeves, each stay rod sleeve configured to receive a corresponding one of the plurality of stay rods.   
     
     
         12 . The linear drive assembly of  claim 1 , in which the second end of the connecting rod comprises a recess, in which the crosshead is at least partially situated within the recess. 
     
     
         13 . The linear drive assembly of  claim 1 , further comprising a pony rod attached to the crosshead. 
     
     
         14 . The linear drive assembly of  claim 1 , in which the crosshead further comprises upper and lower ends each having a convex shape. 
     
     
         15 . The linear drive assembly of  claim 1 , further comprising:
 a bearing situated within the first end of the connecting rod, the bearing made of two semi-cylindrical components.   
     
     
         16 . The linear drive assembly of  claim 15 , in which the bearing comprises an inner surface having a lubricant channel formed therein. 
     
     
         17 . A linear drive assembly, comprising:
 a crosshead configured to reciprocate within a guide, the crosshead comprising a bore formed therein;   a connecting rod, comprising:
 a first end; 
 a second end comprising a plurality of linking elements, in which each linking element comprises an opening that is aligned with the bore of the crosshead; and 
 a body interconnecting the first end and the second end; 
   a wrist pin situated within the bore and each opening of the plurality of linking elements;   a plate attached to the crosshead, the plate comprising a plurality of grooves formed therein; and   a cylindrical bearing situated within the bore of the crosshead, the bearing having a central opening formed therein; in which the wrist pin is situated within the central opening of the bearing.   
     
     
         18 . The linear drive assembly of  claim 17 , further comprising:
 a first pad and a second pad configured to retain the bearing within the bore of the crosshead; in which the first and second pads are secured to the crosshead by a plurality of fasteners.   
     
     
         19 . The linear drive assembly of  claim 18 , in which the bearing is situated intermediate the first and second pads. 
     
     
         20 . A linear drive assembly, comprising:
 a crosshead configured to reciprocate within a guide, the crosshead comprising a bore formed therein;   a connecting rod, comprising:
 a first end; 
 a second end comprising a plurality of linking elements, in which each linking element comprises an opening that is aligned with the bore of the crosshead; and 
 a body interconnecting the first end and the second end; 
   a wrist pin situated within the bore and each opening of the plurality of linking elements;   a plate attached to the crosshead, the plate comprising a plurality of grooves formed therein; and   a bearing situated within the first end of the connecting rod, the bearing made of two semi-cylindrical components;   in which the bearing is formed from a softer material than the connecting rod.